1992 plymouth voyager and my gas gauge doesn't work

I am assuming you have it back in. If it is still working, I would fasten the plug to something solid to keep t attached. These things can be annoying sometimes especially working under the dash.

Have you checked base fuel pressure with a gauge ? Have you tested the asd relay ?

Here's a link.http://www.autozone.com/autozone/repairinfo/repairguide/repairGuideContent.jsp?pageId=0900c15280215e6c

check fuse instrument panel or gage /cluster

That is the oil pressure gauge not the oil level gauge. Sometimes they can act that way when the oil is thin. When is the last time the oil was changed? Try using a heavier weight oil. When engines wear they require thicker oil. What size engine does you voyager have?

You need to check your main fuses under the hood first and then check them under the driver side dash board.

hi yh the float does or you might have a breakin the wire some where

You have a bad ground, probably at the sending unit on top of tank. Check all fuel system grounds.

There is a relay fuse under the hood. You want to check the relay fuse under the hood then check for a loose connector to the back of your dash. If these are good you'll need to take to someplace to have the ECM checked. This usually cost about $50.00

On-board computer needs to be re-booted.  This is done by disconnecting battery - just the negative post is sufficient - then re-connecting and starting the vehicle.  
My 1992 Voyager did this for the first time after I had owned it for almost 10 years and did it sporadically after that.